Accelerometer data‏

Hi!
I am building an app where I have to compare accelerometer data. That is, I am calculating vectors, and then using cosine similarity to compare them. Now this app is supposed to be cross-platform, I've registered the main data (ie the one that the others compare to) on an Android device, then I launched the app on a Linux (non-Android) device. Even though I am doing the same thing, my similarity is around 0 (it is between -1 - complete opposite and 1 - exactly the same). Could this be due to the platform change, or does Qt perform some kind of normalization?
Thanks.